Atari 400 Green Screen

[Vbruno305]

And how would i check it under load, pull the cover off and test the terminals on the plug with it on?

[bfollowell]

Hopefully, your new PSU will work well. If you want an actual Atari PSU, you can use the search linked below. Your profile doesn't say where you're located, so that link is to the U.S. ebay site.

 

https://www.ebay.com/sch/i.html?_from=R40&_nkw=Atari+(CA014748%2C+C014319%2C+C016804%2C+C017945)&_sacat=0&LH_TitleDesc=0&_sop=15

 

[Vbruno305]

I live in Florida..I would probably use Bests Electronics because I would rather have NEW OLD STOCK if possible 

[machf]

Well, to quote from Best's page on power supplies at https://www.best-electronics-ca.com/power guide.htm#PS

 

Quote

Best Electronics also has a small supply of the even harder to find Repairable / Rebuild able New Atari 400 / 800 / 810 / 822 / 850 / 1050 / 1200XL / XF551 50 watt AC universal Power Supplies in stock.  Again under each rubber foot is a case screw.

 

There you have an 18-Watt one and a 50-Watt one to choose from, I guess that's the  ones they mean...

EDIT: Quick question: do you have a working disk drive at hand? Their power supplies are the same as the one for the 400, so you could use one of those to test if the computer alone still displays only a green screen... and try to identify defective boards accordingly.

Edited May 30, 2022 by machf

[Vbruno305]

Ok, new ps came in and now it will sometimes start with a Green Screen and sometimes it will flash the Memo Pad and 1 lucky time i got a stable screen on the memo pad and could type.  What should my next thing be to fix this issue?  

[TGB1718]

I think the first step is to re-seat any chips that are socketed and the RAM and CPU boards, just

to eliminate any possible corrosion causing problems.

 

Are you happy to open it up and do this sort of thing ?

[Vbruno305]

Just now, TGB1718 said:

I think the first step is to re-seat any chips that are socketed and the RAM and CPU boards, just

to eliminate any possible corrosion causing problems.

 

Are you happy to open it up and do this sort of thing ?

Very comfortable...I've been an IT Tech for 25 years, and I mod video game systems...i just do not know what to do here ..i also already reseated the boards so I will do the chips next

[TGB1718]

Just now, Vbruno305 said:

Very comfortable...I've been an IT Tech for 25 years, and I mod video game systems...i just do not know what to do here ..i also already reseated the boards so I will do the chips next

Cool, worth asking

 

[Vbruno305]

10 hours ago, TGB1718 said:

Cool, worth asking

 

I pulled every chip on the ram and rom cards and all chips on the motherboard used detoxit on both the sockets and the chip pins, replaced all chips and inspected them for proper seating after I air dried everything and the same result, Green Screen and if I flip the power on and off I will get a very grainy memo pad or if the only cart i have is in I can kinda make out basketball court.  FRUSTRATING...i even tried adjusting the knob on the rom card all that did was take the green screen to blue or red